Differential Diagnosis for Cough when First Putting on a CPAP Mask

• Single Most Likely Diagnosis
  • Aerophagia or Swallowing Air: This is a common issue when first starting CPAP therapy. The pressure from the mask can cause the user to swallow air, leading to discomfort and coughing.
• Other Likely Diagnoses
  • Dry Air: CPAP machines can dry out the airways, causing irritation and coughing, especially if a humidifier is not used.
  • Allergic Reaction to Mask Materials: Some individuals may be allergic to the materials used in the CPAP mask, such as latex or silicone, which can cause an allergic reaction leading to coughing.
  • Incorrect Mask Fit: A mask that is too tight or too loose can cause air to leak, leading to dryness and irritation in the airways, resulting in coughing.
• Do Not Miss Diagnoses
  • Pulmonary Embolism: Although rare, a pulmonary embolism can cause sudden onset of cough and shortness of breath, which could be exacerbated by the use of a CPAP mask.
  • Pneumonia: An underlying pneumonia could be irritated by the CPAP therapy, leading to coughing.
  • Asthma or COPD Exacerbation: Pre-existing respiratory conditions like asthma or COPD could be triggered or worsened by the CPAP therapy, leading to coughing.
• Rare Diagnoses
  • Laryngospasm: A rare but possible cause of coughing when putting on a CPAP mask, laryngospasm is a sudden, severe contraction of the vocal cords.
  • Gastroesophageal Reflux Disease (GERD): GERD can cause stomach acid to flow up into the throat, irritating the airways and causing coughing, which might be exacerbated by the pressure from the CPAP mask.